The planetary correspondences could be considered the most important of correspondences. This is because all correspondences begin at the planetary level. All the other correspondences are based on planetary connects.

Below you will find the seven classical planets known to the ancients. For more detail on any of these, please visit their corresponding page.

As the introductory paragraph states "Below you will find the seven classical planets known to the ancients" These include the Sun and Moon, but not Uranus, Neptune and Pluto.They have few correspondences because they are modern additions and don't have the alchemical history the others do. Those correspondences that they do have usually overlap with the other planets.
That being said Uranus, Neptune and Pluto are covered elsewhere.